Recipe Instructions Put the leeks and 1/2 cup of the chicken broth in a large pot. Bring to a simmer, and cook 1 minute over moderately-high heat. Add the sweet potatoes and cook 4 more minutes. Add 6 cups of water, reduce the heat to medium, and cook until the sweet potatoes are soft, about 25 minutes. Transfer the mixture to a food processor or blender and blend until smooth, adding as much of the additional chicken broth as you need to make a soup consistency. Return it to the pot and stir in the lime juice, salt, and pepper to taste. Reheat. Serve in warm bowls, garnishing each serving with a little chopped cilantro. This recipe yields 12 servings. Nutritional Information Per Serving: calories: 180; carbohydrates: 41 g; fiber: 5 g; fat: less than 1 g.